I have a 2000 GMC Jimmy Diamond Edition and I bought it used a little over a year ago and the interior is perfect, paint is very good, everything works. However there are some pretty rusty area's underneath. Yesterday I removed all the body bolts and rubber bushings the bolts were very rusty, the top of the rubber mounts rusty and on the frame where the bushing goes the factory sealed it with some kind of tape. But, water must have gotten between the tape and the mounts because it was very rusty. I recently got a blast cabinet so I blasted all the parts inside the cabinet to bare metal. On the body side I used sand paper and steel wool then wiped it down, painted it with rust converter then rustoleum primer and then top coated with rustoleum industrial High Gloss Enamel. Once everything was painted and cured I coated it all with wheel bearing grease and re-assembled everything. I also chased the threads in the body with a tap. The Enamel provides a hard surface and the grease should inhibit any corosion in the future. Today, I removed the transmount and it was in the same condition, the rubber coating around the metal block was worn away and the exposed metal was very rusty. Blasted it to bare metal primed it and painted it with the High Gloss Enamel. It is funny that there is not rust on the body underneath just some of the components.